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51.
Despite the widely acknowledged role of start-ups in economic development, little is known about their innovative activities compared with those of established firms. Drawing on a sample of 12,209 UK firms, we differentiate between services and manufacturing firms and, using a matching estimator approach, demonstrate that start-ups differ significantly from established firms in their innovation activities. We find that in services, being a start-up increases the likelihood of product innovations. However, in manufacturing, we find no significant differences in the likelihood of product innovation between start-ups and established firms. When examining the returns to innovation, we find that start-ups have a significant advantage both in services and in manufacturing. We explore the implications of these results for theory and policy.  相似文献   
52.
In the past decade, research on learning trajectories has progressed from an agenda for research on student learning to include an agenda for research on teaching. In this paper, we use a design experiment to examine a professional development program created to support teacher learning of one learning trajectory. Using a re-interpretation of Ball and colleagues’ mathematics knowledge for teaching framework, we conducted a retrospective analysis to examine how a purposefully selected sample of three teachers used their knowledge to participate in discussions of the professional learning tasks designed to support teacher learning of the trajectory. Findings indicate that professional learning tasks focusing on pedagogical content knowledge present in learning trajectories also allow for teacher learning of subject matter knowledge; this learning is mediated by teachers’ prior mathematics knowledge for teaching. We conclude with considerations for researchers and professional developers seeking to support teachers in learning about learning trajectories.  相似文献   
53.

Introduction:

Blood collection through intravenous lines frequently causes spurious hemolysis. Due to specific structure, the tube holder Holdex® (Greiner Bio-One GmbH, Kremsmuenster, Austria) is supposed to prevent erythrocyte injury in samples collected from catheters, so that we planned a specific study to support this hypothesis.

Materials and methods:

Blood was collected from emergency department (ED) patients with 20-gauge catheter. In patients with odd order numbers, first and second tubes were collected with conventional holder (BD Vacutainer One Use Holder, Becton Dickinson, Milan, Italy) and the third with Holdex, whereas in even patients first and second tubes were drawn with Holdex and the third using BD Vacutainer One Use Holder. The first tube was discarded, whereas the second and third were centrifuged and serum was tested for potassium, lactate dehydrogenase (LD) and hemolysis index.

Results:

The final study population consisted in 60 ED patients. Concentrations of potassium (4.25 vs. 4.16 mmol/L; P = 0.031), LD (498 vs. 459 U/L; P = 0.039) and cell-free hemoglobin (0.42 vs. 0.22 g/L; P = 0.042) were higher in samples collected with BD Vacutainer One Use Holder than with Holdex. The mean bias of cell-free hemoglobin was −0.4 g/L in samples collected with Holdex. Although the frequency of samples with cell-free hemoglobin > 0.5 g/L was identical (17/60 vs. 17/60; P = 1.00), the frequency of those with concentrations >3.0 g/L was higher using BD Vacutainer One Use Holder than Holdex (4/60 vs. 0/60; P = 0.042).

Conclusions:

The use of Holdex for drawing blood from intravenous lines may be effective for reducing gross hemolysis.  相似文献   
54.
Abstract

In two studies, the role of nature experiences and social norms during childhood is explored next to adulthood biospheric values, connectedness to nature, environmental identity, and objective knowledge in relation to pro-environmental behaviors. Study 1 (N?=?185) tested the hypothesized model in the realm of general pro-environmental behaviors and sustainable fruit consumption on a sample of students. Study 2 (N?=?155) tested the model in the realm of sustainable seafood consumer choice on a general population sample. Path analyses show consistent results across samples. Results show that childhood nature experiences and exposure to pro-environmental social norms during childhood are related to adulthood development of connectedness with nature and biospheric values; these, in turn, help in shaping adulthood environmental self-identity ultimately influencing the enactment of sustainable food choices during adulthood. These findings point toward the relevance of childhood experiences for pro-environmental behaviors as compared to the provision of information. The role of objective knowledge across samples is inconsistent, thus requiring future investigations.  相似文献   
55.
ABSTRACT

Deep reading comprehension refers to the process required to succeed at tasks defined by the Common Core State Literacy Standards, as well as to achieve proficiency on the more challenging reading tasks in the Program for International Student Assessment (PISA) framework. The purpose of this study was to test the hypothesis that three skill domains not frequently attended to in instruction or in theories of reading comprehension—academic language, perspective taking, and complex reasoning—predict outcomes on an assessment of deep reading comprehension. The Global Integrated Scenario-based Assessment (GISA; O'Reilly, Weeks, Sabatini, Halderman, & Steinberg, 2014 O'Reilly T., Weeks, J., Sabatini, J., Halderman, L., & Steinberg, J. (2014). Designing reading comprehension assessments for reading interventions: How a theoretically motivated assessment can serve as an outcome measure. Educational Psychology Review, 26, 403424. doi:10.1007/s10648-014-9269-z[Crossref], [Web of Science ®] [Google Scholar]) is designed to reflect students' abilities to evaluate texts, integrate information from an array of texts, and use textual evidence to formulate a position, all features of deep reading comprehension. We tested the role of academic language, perspective taking, and complex reasoning in explaining variance in end-of-year GISA scores, controlling for beginning-of-year scores and student demographics. All three predictors explained small, but significant, amounts of additional variance. We suggest that these three skill domains deserve greater attention in theories of reading comprehension and in instruction.  相似文献   
56.
57.
Background: Physical activity and self-rated wellbeing have important benefits to health. However, scientific knowledge regarding their relationship among older adults is scarce. Thus, the aim of this study was to examine the associations between physical activity frequency and several dimensions of self-rated wellbeing, in a representative sample of European older adults from 28 countries. Methods: This study is based on the European Social Survey round 6, 2012. It had a total sample size of 12,341 older adults (5100 men, 7241 women) with mean age 73.8?±?6.6 years. Information was collected through a questionnaire, filled-in during an hour-long face-to-face interview. Physical activity was accessed using the question “On how many of the last 7 days you were physically active continuously for 20 minutes or longer?” and six dimensions of self-rated wellbeing were used. Results: Physical activity in the last 7 days was linearly related with all dimension of the self-rated wellbeing and with wellbeing total score for both sexes (men, β?=?0.09, 95% CI: 0.07 to 0.10, p?β?=?0.10, 95% CI: 0.09 to 0.11, p?Conclusions: Physical activity promotion should be stressed as a meaningful strategy to improve people's wellbeing overall. This strategy has special importance when considering the older adult population.  相似文献   
58.
This study deals with the post-treatment evaluation of the elastic crossbar system already designed and installed on the recently restored panel painting Deposition from the Cross by an anonymous artist from Abruzzo (sixteenth century). After the restoration, the panel and the crossbars were subjected to mechanical tests to identify their elastic characteristics. Then the panel, equipped with the elastic crossbar system, was subjected for about two months to controlled environmental cycles made up of approximately constant humidity periods. During the two months, the forces exerted by the springs and the deformations of both panel and crossbars were continuously monitored. A mathematical model, calibrated on the specific parameters derived from the analysis of the panel, provided the deformation that the panel would have shown without the crossbars; comparing the model output with the measured data provided a restraining effect (RE) of approximately 7% (RE could range between zero – no restraint – and 100% – total restraint). Future developments of this project will define appropriate procedures to design an elastic crossbar system for a given panel, once the expert judgement of restorers has identified the most desirable RE to be achieved.  相似文献   
59.
Professional services firms survive by exploiting the skills and knowledge of their employees to deliver a range of projects for clients. As a result of working on these projects, an organization's capabilities evolve in unpredictable and often divergent ways. In order to help their staff conduct these projects, services firms have invested heavily in knowledge management systems. To date, few attempts have been made to use the information contained in these knowledge management systems to understand the nature and evolution of capabilities in professional services firms. Using the expert yellow pages of Arup, one of the world's leading engineering consultancies, we develop a new approach based on co-word and proximity analysis to map the knowledge and skills of professional services firms. This approach provides a mechanism to allow such firms to better understand what they know and help them to deploy their skills in new and potentially lucrative ways.  相似文献   
60.
What is the place of social theory in mathematics education research, and what is it for? This special issue of Educational Studies in Mathematics offers insights on what could be the role of some sociological theories in a field that has historically privileged learning theories coming from psychology and mathematics as the main theoretical frames informing research. Although during the last 10 years the term “socio-cultural” has become part of the accepted and widespread trends of mathematics education research when addressing learning, this issue gathers a collection of papers that depart from a “socio-cultural” approach to learning and rather deploy sociological theories in the analysis of mathematics education practices. In this commentary paper, we will point to what we see to be the contributions of these papers to the field. We will do so by highlighting issues that run through the six papers. We will try to synthetize what we think are the benchmarks of the social approach to mathematics education that they propose. We will also take a critical stance and indicate some possible extensions of the use of social theory that are not addressed in this special issue but nonetheless are worth being explored for a fuller understanding of the “social” in mathematics education.  相似文献   
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